# Apache Airflow: the Core API logout endpoint revokes only a session token presented as the \_token cookie. When a client logs out presenting its credential as an Authorization bearer header instead,...

Advisory record · `PYSEC-2026-3990`

- **Identifiers:** `PYSEC-2026-3990` · `BIT-airflow-2026-86473` · `CVE-2026-86473`
- **State:** Confirmed
- **Severity:** CVSS 9.1 Critical
- **Critical:** Yes: CVSS 9+
- **Weakness (CWE):** [CWE-613](https://cwe.mitre.org/data/definitions/613.html)
- **Tags:** [Authentication bypass](https://agentprime.io/advisories/tag/auth-bypass.md)
- **Published:** 21 Sept 2026
- **Updated:** 26 Sept 2026
- **Reviewed by a person:** No

Published by OSV at 21 Sept 2026, 15:17 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

## Critical

Critical, because:

- CVSS score 9.1: 9.0 or more.

How we decide what’s critical: <https://agentprime.io/advisories/critical.md>

## Affected packages

- `apache-airflow` (PyPI): affected `>=3.0.0, <3.3.2`; fixed in `3.3.2`

## Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

> Apache Airflow versions 3.0.0 before 3.3.2 are affected. When a client logs out with its token sent as an Authorization bearer header, the Core API logout endpoint returns a normal response but does not revoke the token, so it stays valid until it expires (24 hours by default). An attacker who already holds a copy of a valid token can keep access after the victim logs out, though they gain no privileges beyond the victim's own. Upgrade to apache-airflow 3.3.2 or later.

Written 1 Nov 2026.

## Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

## Severity and exploitation

- 9.1 Critical, CVSS 3.1: `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N`, from OSV

- **CISA KEV:** Not listed.
- **EPSS:** 0.0075, the 55th percentile, on 12 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

- 21 Sept 2026, 14:33 UTC: [Confirmed by the CVE List](https://www.cve.org/CVERecord?id=CVE-2026-86473)
- 21 Sept 2026, 15:17 UTC: [Confirmed by NVD](https://nvd.nist.gov/vuln/detail/CVE-2026-86473)
- 31 Oct 2026, 14:09 UTC: First seen by agentprime
- 31 Oct 2026, 14:09 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/PYSEC-2026-3990)

## Sources

- [OSV: PYSEC-2026-3990](https://osv.dev/vulnerability/PYSEC-2026-3990)
- <http://www.openwall.com/lists/oss-security/2026/09/21/5>
- <https://lists.apache.org/thread/k9z1p0q1ng8m68nlnv9d1fqzscrfm7vr>

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.

## Check whether this affects you

A Match means an installed version is in the affected range above. Most don’t affect the app; agentprime hasn’t analysed this one yet.

- With the agentprime MCP server (<https://api.agentprime.io/mcp>), ask your agent to check the project: `check_lockfile` sends a lockfile, `check_packages` a list of installed packages, and both return the Matches and the upgrades that clear them. `get_advisory` returns this record. Setup: <https://agentprime.io/mcp.md>
- In a browser: <https://agentprime.io/check/> reads your lockfile in the browser, never uploading it.
- Whether it touches your code, with file and line: the Claude Code plugin, <https://agentprime.io/plugin.md>
- As JSON: <https://api.agentprime.io/v1/advisories/PYSEC-2026-3990>, or `POST https://api.agentprime.io/v1/match` with your packages (<https://agentprime.io/api.md>)

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The web page: <https://agentprime.io/advisories/PYSEC-2026-3990/>. Everything for agents: <https://agentprime.io/llms.txt>.